Enhanced piezoelectric properties and strain response in 〈001〉 textured BNT-BKT-BT ceramics

• Published in: Materials & design Vol. 137; pp. 184 - 191
• Main Authors: Zhao, Zhi-Hao, Ye, Meng-Yang, Ji, Hui-Ming, Li, Xiao-Lei, Zhang, Xiaowen, Dai, Yejing
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 05.01.2018
• Subjects: Ferroelectric properties; Lead-free ceramics; Phase transition; Piezoelectric properties; Strain response; Strain response; Piezoelectric properties; Lead-free ceramics; Ferroelectric properties; Phase transition
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2017.10.003

Highly 〈001〉 textured (~81%) ternary BNT-BKT-BT ceramics are prepared by reactive templated grain growth (RTGG) method with plate-like Bi4Ti3O12 particles as templates. Outstanding electric properties, which are both higher than state of art BNT-based ceramics, emerge in the aforementioned sample due to the grain orientation. For the textured ceramics, a high piezoelectric constant d33 of 314pC/N could be obtained, which is ~1.4-fold larger than that of a random one (221pC/N). A high electro-strain response (~0.41%) is obtained at a low applied electric field (4kV/mm) in textured ceramics, with the normalized strain d33⁎ (Smax/Emax)=1030pm/V near the TF-R (the temperature of ferroelectric to ergodic relaxor state transition). Moreover, the evolution process of relaxor phases is studied. The texture technique also could improve the TF-R from 70°C to 100°C, enhancing the temperature stability. In addition, the polarization switching process in ferroelectric phase and ergodic relaxor state are analyzed in this work, respectively. [Display omitted] •High piezoelectric constant and electro-strain response could be obtained in textured Na0.5Bi0.5TiO3 ceramics.•Defect dipole would stabilize ferroelectric domains and polar nanoregions under applied electric field.•The electric-field-induced transition could appear at lower electric field for textured Na0.5Bi0.5TiO3 ceramics.